What is the appropriate regimen for prescribing oral progesterone (e.g. norethindrone, medroxyprogesterone acetate) to delay a period in a female patient of reproductive age with a regular menstrual cycle and no underlying medical conditions?

Prescribing Oral Progesterone to Delay Menstruation

For menstrual delay in a reproductive-age woman with regular cycles, prescribe norethindrone acetate 5 mg three times daily, starting 3-5 days before the expected period and continuing until menstruation is desired, at which point withdrawal bleeding will occur 2-3 days after stopping.

Recommended Regimen

• Norethindrone acetate 5 mg orally three times daily (total 15 mg/day) is the standard regimen for menstrual postponement 1
• Begin administration 3-5 days before the expected menstrual period to ensure adequate progestogenic effect on the endometrium 1
• Continue daily without interruption for the duration menstruation needs to be delayed 2
• Withdrawal bleeding typically occurs 2-3 days after discontinuation of the medication 1

Alternative Progestogen Options

• Medroxyprogesterone acetate 10 mg three times daily can be used as an alternative, though it has a less favorable metabolic profile than norethindrone 3, 1
• Norethindrone acetate is preferred over medroxyprogesterone acetate due to superior cardiovascular and metabolic outcomes while maintaining excellent endometrial control 4
• The relative potency of norethindrone is approximately 10 times that of medroxyprogesterone acetate, which explains the dosing differences 1

Critical Timing Considerations

• Do not start progesterone after menstruation has already begun—it will not stop active bleeding and may cause irregular spotting 5
• Starting too early (more than 5 days before expected menses) unnecessarily prolongs exposure without additional benefit 1
• The medication must be taken at the same time each day to maintain stable progestogenic suppression of endometrial shedding 2

Duration and Safety Limits

• Limit continuous use to a maximum of 2-3 weeks to minimize thrombotic risk, particularly with higher doses of norethindrone 4
• Prolonged continuous progestogen use (>6 months) carries increased risk of meningioma and should be avoided for menstrual delay purposes 4
• For patients with personal or family history of venous thromboembolism, consider alternative strategies or use the lowest effective duration 4

Common Pitfalls to Avoid

• Never use progestin-only contraceptive pills (0.35 mg norethindrone) for menstrual delay—the dose is far too low to suppress menstruation 6, 2
• Avoid medroxyprogesterone acetate depot injection for menstrual delay, as its prolonged action makes timing of withdrawal bleeding unpredictable 5
• Do not prescribe oral micronized progesterone for menstrual delay—its bioavailability is poor and inconsistent, requiring doses of 200-400 mg daily that cause significant sedation and dizziness 7, 8

Patient Counseling Points

• Inform patients that breakthrough bleeding or spotting may occur despite treatment, particularly if doses are missed 2
• Advise taking the medication with food if nausea occurs, though this is less common with norethindrone than with oral micronized progesterone 8
• Warn that menstruation will resume 2-3 days after stopping, so plan discontinuation accordingly 1
• This is a short-term intervention only—it does not provide contraception and should not be used as a contraceptive method 2